Electronic device for charging battery based on voltage of interface and method for controlling same

ABSTRACT

Disclosed are an electronic device for charging a battery based on a voltage of an interface and a method for controlling the same. The electronic device for charging a battery based on a voltage of an interface, according to an embodiment, may include: an interface comprising a conductive piece, a current reference control circuit; and a charging current control circuit configured to control the magnitude of a charging current applied to the interface, based on a control signal resulting from a comparison between a charging current value applied to the interface and a first critical current value configured in the current reference control circuit, wherein the current reference control circuit is configured to, based on a voltage value applied to the interface reaching a first critical voltage value, gradually decrease the first critical current value until the voltage value applied to the interface falls below the first critical voltage value, and maintain the first critical current value based on the voltage value applied to the interface being less than the first critical voltage value.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/KR2021/019269 designating the United States, filed on Dec. 17, 2021,filed in the Korean Intellectual Property Receiving Office and claimingpriority to Korean Patent Application No. 10-2020-0182455, filed on Dec.23, 2020, in the Korean Intellectual Property Office, the disclosures ofwhich are incorporated by reference herein in their entireties.

BACKGROUND Field

The disclosure relates to an electronic device for charging a batterybased on a voltage of an interface, and a method for controlling thesame.

Description of Related Art

There has been increasing use of electronic devices that are easy tocarry, such as smartphones, tablet PCs, and wearable devices, andelectronic devices have also been developed to be worn by users, in linewith ever-increasing use of electronic devices, such that portabilityand user accessibility can be improved. As an example of such electronicdevice, an ear-wearable device (for example, earphone) can be worn onthe user's ear, and such an electronic device may be driven by achargeable/dischargeable battery.

Power may be supplied from a charging device (for example, cradle) usingan interface (for example, POGO pin) provided on the housing of anelectronic device (for example, ear-wearable device). If the batteryvoltage rises nearly to a fully-charged level, the ear-wearable devicemay execute charging with a predetermined voltage. For example, if thebattery voltage reaches the target voltage in a constant currentcharging type, the charging mode may switch to a constant voltagecharging type in which the current is reduced to suppress voltageincrease, in order to guarantee that charging proceeds further withoutincreasing the voltage.

A communication IC that uses a separate V_BUS may be added, or aseparate element (for example, separate POGO terminal) may be added, inorder to detect whether or not the battery voltage of the ear-wearabledevice reaches the target voltage, and to change the charging modeaccordingly, but such an approach may increase the occupied area andincrease the implementation cost in the case of an ear-wearable devicewhich is aimed at compactness. In addition, if the ear-wearable devicereceives power through electric connection with a connection terminal(for example, POGO pin) of a charging device, there is insufficientspace to allocate a separate pin. If constant-current charging andconstant-voltage charging are performed based on a voltage output by acharging circuit (for example, charger of charging cradle), the outputvoltage of the charging circuit (for example, charger of chargingcradle) reaches the target voltage before the battery voltage (forexample, VCELL) reaches the target voltage, as the output voltage (forexample, VCHGO) of the charging circuit is supplied to the battery. Inthis case, the charging current (ICELL) decreases, and such a chargingtype may require a long charging time. If a separate interface isallocated, or if power line communication is used, the electronic device(for example, charging cradle) may be difficult to implement, or mayrequire an increased cost, because the separate pin for detecting thebattery charging state or the additional element (for example, powerline communication IC) increases the mounting space.

If a fixed voltage is applied, instead of allocating a separateinterface, such that a linear charger included in an external electronicdevice senses the battery voltage/current, thereby charging the batteryof the external electronic device through aconstant-voltage/constant-current function, a relatively largedifference between the interface voltage and the battery voltage may bemaintained, and such a voltage difference may result in charging loss.

SUMMARY

Embodiments of the disclosure provide an electronic device capable ofsubstantially reducing charging loss compared with FIG. 1C whileexhibiting a charging performance substantially identical to thecharging type illustrated in FIG. 1B or FIG. 1C without adding aseparate interface for battery cell sensing other than conventionalinterfaces (for example, V_BUS terminal and GNG terminal) provided inthe electronic device (for example, charging cradle) (in other words,without having to acquire battery cell voltage information by theelectronic device (for example, charging cradle)).

Embodiments of the disclosure provide an electronic device capable ofreducing charging loss, wherein the magnitude of charging current forcharging the battery of an ear-wearable device is controlled withreference to whether or not an interface voltage (for example, POGOvoltage) has reached a predesignated voltage (for example, firstcritical voltage), thereby reducing the difference between the chargingvoltage (VCHGO) and the battery cell voltage (VCELL) compared with theprior art.

Embodiments of the disclosure provide a method for controlling anelectronic device, wherein a battery charging function or operation canbe performed in such a manner that charging loss is substantiallyreduced compared with the charging type illustrated in FIG. 1C withoutadding a separate interface for battery cell sensing other thanconventional interfaces (for example, V_BUS terminal and GNG terminal)provided in the electronic device (for example, charging cradle) (inother words, without having to acquire battery cell voltage informationby the electronic device (for example, charging cradle)).

Embodiments of the disclosure provide a method for controlling anelectronic device capable of reducing charging loss, wherein themagnitude of charging current for charging the battery of anear-wearable device is controlled with reference to whether or not aninterface voltage (for example, POGO voltage) has reached apredesignated voltage (for example, first critical voltage), therebyreducing the difference between the charging voltage (VCHGO) and thebattery cell voltage (VCELL) compared with the prior art.

An electronic device according to an example embodiment of thedisclosure may include: an interface including a conductive piece, acurrent reference control circuit, and a charging current controlcircuit configured to control a magnitude of a charging current appliedto the interface based on a control signal resulting from a comparisonbetween a charging current value applied to the interface and a firstcritical current value of the current reference control circuit, whereinthe current reference control circuit is configured to graduallydecrease the first critical current value based on a voltage valueapplied to the interface reaching a first critical voltage value, andmaintain the first critical current value based on the voltage valueapplied to the interface being less than the first critical voltagevalue.

An electronic device according to an example embodiment of thedisclosure may include: an interface including a conductive piece and apower adjustment circuit, wherein the power adjustment circuit isconfigured to gradually increase and output a charging current value forcharging a battery of an external electronic device, while theelectronic device and the external electronic device contact through theinterface, based on a voltage value applied to the interface reaching afirst critical voltage value according to output of the chargingcurrent, charge the battery while gradually decreasing the chargingcurrent value until the voltage value applied to the interface dropsbelow the first critical voltage value, based on the voltage valueapplied to the interface again reaching the first critical voltage valuewhile the battery is charged with the gradually reduced charging currentvalue, additionally reduce the reduced charging current value, based onthe additionally reduced charging value reaching a termination currentvalue, stop output of the charging current, and based on theadditionally reduced charging value exceeding the termination currentvalue, the battery is charged with the additionally reduced chargingcurrent value.

A method for controlling an electronic device according to an exampleembodiment of the disclosure may include: based on a voltage valueapplied to an interface of the electronic device reaching a firstcritical voltage value, gradually decreasing the first critical currentvalue by a current reference control circuit of the electronic deviceuntil the voltage value applied to the interface falls below the firstcritical voltage value, and maintaining the first critical current valueby the current reference control circuit of the electronic device basedon the voltage value applied to the interface being less than the firstcritical voltage value, wherein the electronic device includes acharging current control circuit configured to control a magnitude of acharging current applied to the interface, based on a control signalresulting from a comparison between a charging current value applied tothe interface and the first critical current value of the currentreference control circuit.

Various example embodiments of the disclosure may provide an electronicdevice capable of performing a battery charging function or operation insuch a manner that charging loss is substantially reduced without addinga separate interface for battery cell sensing other than conventionalinterfaces (for example, V_BUS terminal and GNG terminal) provided inthe electronic device (for example, charging cradle) (in other words,without having to acquire battery cell voltage information by theelectronic device (for example, charging cradle)).

Various example embodiments of the disclosure may provide an electronicdevice capable of reducing charging loss, wherein the magnitude ofcharging current for charging the battery of an ear-wearable device iscontrolled with reference to whether or not an interface voltage (forexample, POGO voltage) has reached a predesignated voltage (for example,first critical voltage), thereby reducing the difference between thecharging voltage (VCHGO) and the battery cell voltage (VCELL).

It will be apparent to those skilled in the art that advantageouseffects resulting from various embodiments are not limited to theabove-described advantageous effects, and various advantageous effectsare incorporated in the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of certainembodiments of the present disclosure will be more apparent from thefollowing detailed description, taken in conjunction with theaccompanying drawings, in which:

FIG. 1A is a diagram illustrating a function or an operation ofperforming constant current charging and constant voltage charging basedon a voltage output by a charging circuit (e.g., a charger of a chargingcradle);

FIG. 1B is a diagram illustrating a function or an operation ofperforming cell sensing with addition of a separate interface other thana conventional interface and performing charging based on a voltage of abattery cell sensed by the cell sensing;

FIG. 1C is a diagram illustrating a function or an operation of applyinga fixed voltage to an interface without adding a separate interfaceother than a conventional interface and directly performing cell sensingby a linear charger included in an external electronic device (in otherwords, an ear-wearable device) to charge a battery of the externalelectronic device;

FIG. 2 is a block diagram illustrating an example configuration of anelectronic device in a network environment according to variousembodiments;

FIG. 3A is a diagram illustrating an example charging system forcharging a battery according to various embodiments;

FIGS. 3B and 3C are diagrams illustrating an example charging device andan ear-wearable device according to various embodiments;

FIG. 4 is a block diagram illustrating an example configuration of afirst charger included in a charging device according to variousembodiments;

FIG. 5 is a block diagram illustrating an example configuration of asecond charger included in an ear-wearable device according to variousembodiments;

FIG. 6 is diagram flowchart illustrating an example operation ofstopping charging of an external electronic device (e.g., anear-wearable device) when a charging current value output from acharging device reaches a termination current value according to variousembodiments;

FIG. 7 includes graphs illustrating an example operation of charging abattery according to the operation illustrated in FIG. 6 according tovarious embodiments;

FIG. 8 is a circuit diagram illustrating an example configuration of afirst charger and a second charger according to various embodiments; and

FIG. 9 is a flowchart illustrating an example operation of increasingresistance of a MOSFET included in a second charger according to variousembodiments.

DETAILED DESCRIPTION

Referring to FIG. 1A, a time interval before T1 illustrated in FIG. 1Amay be a constant current charging interval, and a time interval from T1to T2 may be a constant voltage charging interval. In the case in whichconstant current charging and constant voltage charging are performedbased on a voltage that is output by a charging circuit (e.g., a chargerof a charging cradle), when the output voltage (e.g., VCHGO) of thecharging circuit is supplied to a battery, the output voltage of thecharging circuit (e.g., the charger of the charging cradle) reaches atarget voltage before a voltage (e.g., VCELL) of the battery reaches thetarget voltage, and thus a charging current (ICELL) is reduced. In thecase of this charging method, a charging time may be long.

Referring to FIG. 1B, when a separate interface is allocated or powerline communication is used, a mounting space may be increased due toadditional elements such as a separate pin or power line communicationIC for detecting the state of charging of a battery, and thus anelectronic device (e.g., a charging cradle) is difficult to implement,or costs may be increased.

Referring to FIG. 1C, when a fixed voltage is applied without allocatinga separated interface and a linear charger included in an externalelectronic device senses a battery voltage/current and charges a batteryof the external electronic device through a constant voltage/constantcurrent function, the difference between an interface voltage and abattery voltage may be remain relatively large, and thus this voltagedifference may result in charging loss.

FIG. 2 is a block diagram illustrating an example electronic device 201in a network environment 200 according to various embodiments. Referringto FIG. 2, the electronic device 201 in the network environment 200 maycommunicate with an electronic device 202 via a first network 298 (e.g.,a short-range wireless communication network), or at least one of anelectronic device 204 or a server 208 via a second network 299 (e.g., along-range wireless communication network). According to an embodiment,the electronic device 201 may communicate with the electronic device 204via the server 208. According to an embodiment, the electronic device201 may include a processor 220, memory 230, an input module 250, asound output module 255, a display module 260, an audio module 270, asensor module 276, an interface 277, a connecting terminal 278, a hapticmodule 279, a camera module 280, a power management module 288, abattery 289, a communication module 290, a subscriber identificationmodule (SIM) 296, or an antenna module 297. In various embodiments, atleast one of the components (e.g., the connecting terminal 278) may beomitted from the electronic device 201, or one or more other componentsmay be added in the electronic device 201. In various embodiments, someof the components (e.g., the sensor module 276, the camera module 280,or the antenna module 297) may be implemented as a single component(e.g., the display module 260).

The processor 220 may execute, for example, software (e.g., a program240) to control at least one other component (e.g., a hardware orsoftware component) of the electronic device 201 coupled with theprocessor 220, and may perform various data processing or computation.According to an embodiment, as at least part of the data processing orcomputation, the processor 220 may store a command or data received fromanother component (e.g., the sensor module 276 or the communicationmodule 290) in volatile memory 232, process the command or the datastored in the volatile memory 232, and store resulting data innon-volatile memory 234. According to an embodiment, the processor 220may include a main processor 221 (e.g., a central processing unit (CPU)or an application processor (AP)), or an auxiliary processor 223 (e.g.,a graphics processing unit (GPU), a neural processing unit (NPU), animage signal processor (ISP), a sensor hub processor, or a communicationprocessor (CP)) that is operable independently from, or in conjunctionwith, the main processor 221. For example, when the electronic device201 includes the main processor 221 and the auxiliary processor 223, theauxiliary processor 223 may be adapted to consume less power than themain processor 221, or to be specific to a specified function. Theauxiliary processor 223 may be implemented as separate from, or as partof the main processor 221.

The auxiliary processor 223 may control, for example, at least some offunctions or states related to at least one component (e.g., the displaymodule 260, the sensor module 276, or the communication module 290)among the components of the electronic device 201, instead of the mainprocessor 221 while the main processor 221 is in an inactive (e.g.,sleep) state, or together with the main processor 221 while the mainprocessor 221 is in an active (e.g., executing an application) state.According to an embodiment, the auxiliary processor 223 (e.g., an imagesignal processor or a communication processor) may be implemented aspart of another component (e.g., the camera module 280 or thecommunication module 290) functionally related to the auxiliaryprocessor 223. According to an embodiment, the auxiliary processor 223(e.g., the neural processing unit) may include a hardware structurespecified for artificial intelligence model processing. An artificialintelligence model may be generated by machine learning. Such learningmay be performed, e.g., by the electronic device 201 where theartificial intelligence model is performed or via a separate server(e.g., the server 208). Learning algorithms may include, but are notlimited to, e.g., supervised learning, unsupervised learning,semi-supervised learning, or reinforcement learning. The artificialintelligence model may include a plurality of artificial neural networklayers. The artificial neural network may be a deep neural network(DNN), a convolutional neural network (CNN), a recurrent neural network(RNN), a restricted boltzmann machine (RBM), a deep belief network(DBN), a bidirectional recurrent deep neural network (BRDNN), deepQ-network or a combination of two or more thereof but is not limitedthereto. The artificial intelligence model may, additionally oralternatively, include a software structure other than the hardwarestructure.

The memory 230 may store various data used by at least one component(e.g., the processor 220 or the sensor module 276) of the electronicdevice 201. The various data may include, for example, software (e.g.,the program 240) and input data or output data for a command relatedthereto. The memory 230 may include the volatile memory 232 or thenon-volatile memory 234.

The program 240 may be stored in the memory 230 as software, and mayinclude, for example, an operating system (OS) 242, middleware 244, oran application 246.

The input module 250 may receive a command or data to be used by anothercomponent (e.g., the processor 220) of the electronic device 201, fromthe outside (e.g., a user) of the electronic device 201. The inputmodule 250 may include, for example, a microphone, a mouse, a keyboard,a key (e.g., a button), or a digital pen (e.g., a stylus pen).

The sound output module 255 may output sound signals to the outside ofthe electronic device 201. The sound output module 255 may include, forexample, a speaker or a receiver. The speaker may be used for generalpurposes, such as playing multimedia or playing record. The receiver maybe used for receiving incoming calls. According to an embodiment, thereceiver may be implemented as separate from, or as part of the speaker.

The display module 260 may visually provide information to the outside(e.g., a user) of the electronic device 201. The display module 260 mayinclude, for example, a display, a hologram device, or a projector andcontrol circuitry to control a corresponding one of the display,hologram device, and projector. According to an embodiment, the displaymodule 260 may include a touch sensor adapted to detect a touch, or apressure sensor adapted to measure the intensity of force incurred bythe touch.

The audio module 270 may convert a sound into an electrical signal andvice versa. According to an embodiment, the audio module 270 may obtainthe sound via the input module 250, or output the sound via the soundoutput module 255 or an external electronic device (e.g., an electronicdevice 202 (e.g., a speaker or a headphone)) directly or wirelesslycoupled with the electronic device 201.

The sensor module 276 may detect an operational state (e.g., power ortemperature) of the electronic device 201 or an environmental state(e.g., a state of a user) external to the electronic device 201, andthen generate an electrical signal or data value corresponding to thedetected state. According to an embodiment, the sensor module 276 mayinclude, for example, a gesture sensor, a gyro sensor, an atmosphericpressure sensor, a magnetic sensor, an acceleration sensor, a gripsensor, a proximity sensor, a color sensor, an infrared (IR) sensor, abiometric sensor, a temperature sensor, a humidity sensor, or anilluminance sensor.

The interface 277 may support one or more specified protocols to be usedfor the electronic device 201 to be coupled with the external electronicdevice (e.g., the electronic device 202) directly or wirelessly.According to an embodiment, the interface 277 may include, for example,a high definition multimedia interface (HDMI), a universal serial bus(USB) interface, a secure digital (SD) card interface, or an audiointerface.

A connecting terminal 278 may include a connector via which theelectronic device 201 may be physically connected with the externalelectronic device (e.g., the electronic device 202). According to anembodiment, the connecting terminal 278 may include, for example, anHDMI connector, a USB connector, an SD card connector, or an audioconnector (e.g., a headphone connector).

The haptic module 279 may convert an electrical signal into a mechanicalstimulus (e.g., a vibration or a movement) or electrical stimulus whichmay be recognized by a user via his tactile sensation or kinestheticsensation. According to an embodiment, the haptic module 279 mayinclude, for example, a motor, a piezoelectric element, or an electricstimulator.

The camera module 280 may capture a still image or moving images.According to an embodiment, the camera module 280 may include one ormore lenses, image sensors, image signal processors, or flashes.

The power management module 288 may manage power supplied to theelectronic device 201. According to an embodiment, the power managementmodule 288 may be implemented as at least part of, for example, a powermanagement integrated circuit (PMIC).

The battery 289 may supply power to at least one component of theelectronic device 201. According to an embodiment, the battery 289 mayinclude, for example, a primary cell which is not rechargeable, asecondary cell which is rechargeable, or a fuel cell.

The communication module 290 may support establishing a direct (e.g.,wired) communication channel or a wireless communication channel betweenthe electronic device 201 and the external electronic device (e.g., theelectronic device 202, the electronic device 204, or the server 208) andperforming communication via the established communication channel. Thecommunication module 290 may include one or more communicationprocessors that are operable independently from the processor 220 (e.g.,the application processor (AP)) and supports a direct (e.g., wired)communication or a wireless communication. According to an embodiment,the communication module 290 may include a wireless communication module292 (e.g., a cellular communication module, a short-range wirelesscommunication module, or a global navigation satellite system (GNSS)communication module) or a wired communication module 294 (e.g., a localarea network (LAN) communication module or a power line communication(PLC) module). A corresponding one of these communication modules maycommunicate with the external electronic device 204 via the firstnetwork 298 (e.g., a short-range communication network, such asBluetooth™, wireless-fidelity (Wi-Fi) direct, or infrared dataassociation (IrDA)) or the second network 299 (e.g., a long-rangecommunication network, such as a legacy cellular network, a 5G network,a next-generation communication network, the Internet, or a computernetwork (e.g., LAN or wide area network (WAN)). These various types ofcommunication modules may be implemented as a single component (e.g., asingle chip), or may be implemented as multi components (e.g., multichips) separate from each other. The wireless communication module 292may identify or authenticate the electronic device 201 in acommunication network, such as the first network 298 or the secondnetwork 299, using subscriber information (e.g., international mobilesubscriber identity (IMSI)) stored in the subscriber identificationmodule 296.

The wireless communication module 292 may support a 5G network, after a4G network, and next-generation communication technology, e.g., newradio (NR) access technology. The NR access technology may supportenhanced mobile broadband (eMBB), massive machine type communications(mMTC), or ultra-reliable and low-latency communications (URLLC). Thewireless communication module 292 may support a high-frequency band(e.g., the mmWave band) to achieve, e.g., a high data transmission rate.The wireless communication module 292 may support various technologiesfor securing performance on a high-frequency band, such as, e.g.,beamforming, massive multiple-input and multiple-output (massive MIMO),full dimensional MIMO (FD-MIMO), array antenna, analog beam-forming, orlarge scale antenna. The wireless communication module 292 may supportvarious requirements specified in the electronic device 201, an externalelectronic device (e.g., the electronic device 204), or a network system(e.g., the second network 299). According to an embodiment, the wirelesscommunication module 292 may support a peak data rate (e.g., 20 Gbps ormore) for implementing eMBB, loss coverage (e.g., 164 dB or less) forimplementing mMTC, or U-plane latency (e.g., 0.5 ms or less for each ofdownlink (DL) and uplink (UL), or a round trip of 1 ms or less) forimplementing URLLC.

The antenna module 297 may transmit or receive a signal or power to orfrom the outside (e.g., the external electronic device) of theelectronic device 201. According to an embodiment, the antenna module297 may include an antenna including a radiating element including aconductive material or a conductive pattern formed in or on a substrate(e.g., a printed circuit board (PCB)). According to an embodiment, theantenna module 297 may include a plurality of antennas (e.g., arrayantennas). In such a case, at least one antenna appropriate for acommunication scheme used in the communication network, such as thefirst network 298 or the second network 299, may be selected, forexample, by the communication module 290 from the plurality of antennas.The signal or the power may then be transmitted or received between thecommunication module 290 and the external electronic device via theselected at least one antenna. According to an embodiment, anothercomponent (e.g., a radio frequency integrated circuit (RFIC)) other thanthe radiating element may be additionally formed as part of the antennamodule 297.

According to various embodiments, the antenna module 297 may form ammWave antenna module. According to an embodiment, the mmWave antennamodule may include a printed circuit board, an RFIC disposed on a firstsurface (e.g., the bottom surface) of the printed circuit board, oradjacent to the first surface and capable of supporting a designatedhigh-frequency band (e.g., the mmWave band), and a plurality of antennas(e.g., array antennas) disposed on a second surface (e.g., the top or aside surface) of the printed circuit board, or adjacent to the secondsurface and capable of transmitting or receiving signals of thedesignated high-frequency band.

At least some of the above-described components may be coupled mutuallyand communicate signals (e.g., commands or data) therebetween via aninter-peripheral communication scheme (e.g., a bus, general purposeinput and output (GPIO), serial peripheral interface (SPI), or mobileindustry processor interface (MIPI)).

According to an embodiment, commands or data may be transmitted orreceived between the electronic device 201 and the external electronicdevice 204 via the server 208 coupled with the second network 299. Eachof the external electronic devices 202 or 204 may be a device of a sametype as, or a different type, from the electronic device 201. Accordingto an embodiment, all or some of operations to be executed at theelectronic device 201 may be executed at one or more of the externalelectronic devices 202, 204, or 208. For example, if the electronicdevice 201 should perform a function or a service automatically, or inresponse to a request from a user or another device, the electronicdevice 201, instead of, or in addition to, executing the function or theservice, may request the one or more external electronic devices toperform at least part of the function or the service. The one or moreexternal electronic devices receiving the request may perform the atleast part of the function or the service requested, or an additionalfunction or an additional service related to the request, and transferan outcome of the performing to the electronic device 201. Theelectronic device 201 may provide the outcome, with or without furtherprocessing of the outcome, as at least part of a reply to the request.To that end, a cloud computing, distributed computing, mobile edgecomputing (MEC), or client-server computing technology may be used, forexample. The electronic device 201 may provide ultra low-latencyservices using, e.g., distributed computing or mobile edge computing. Inan embodiment, the external electronic device 204 may include aninternet-of-things (IoT) device. The server 208 may be an intelligentserver using machine learning and/or a neural network. According to anembodiment, the external electronic device 204 or the server 208 may beincluded in the second network 299. The electronic device 201 may beapplied to intelligent services (e.g., smart home, smart city, smartcar, or healthcare) based on 5G communication technology or IoT-relatedtechnology.

FIG. 3A is a diagram illustrating an example configuration of a chargingsystem for charging a battery (e.g., a battery module 326) according tovarious embodiments.

Referring to FIG. 3A, a charging device 310 according to an embodimentmay include a charging circuit 318 (e.g., a first charger 400 referringto FIG. 4). The charging circuit according to an embodiment may beelectrically connected to an external electronic device (e.g., anear-wearable device 320) through a pogo pin. The external electronicdevice (e.g., the ear-wearable device 320) according to an embodimentmay include a linear charger 325 (e.g., a second charger 500 referringto FIG. 5) and a battery module (e.g., including a battery) 326. Thecharging circuit 318 according to an embodiment may output a chargingcurrent for charging the battery module 326 to the linear charger 325.The linear charger 325 according to an embodiment may compare a currentsupplied to the battery module 326 (hereinafter, a battery currentvalue) and a battery voltage value with a second critical current valueand a second critical voltage value, respectively, and may adjust (e.g.,increase), based on the result of the comparison a resistance value of aMOSFET 510 (refer to FIG. 5) included in the linear charger 325. Thecharging circuit 318 according to an embodiment may adjust and outputthe magnitude of a charging current based on a voltage applied to thepogo pine, changed depending on the adjustment of the resistance valueof the MOSFET 510. The above-described function or operation of thedisclosure will be described in greater detail below with reference toFIGS. 4 and 5.

FIGS. 3B and 3C are diagrams illustrating an example charging device 310and an example ear-wearable device 320 according to various embodiments.According to an embodiment, the ear-wearable device 320 may also bereferred to as an earphone, an ear piece, an ear bud, or a hearingdevice, or the like. Further, the charging device 310 according to anembodiment may be referred to as a charging cradle or a charging case,or the like.

According to an embodiment, the ear-wearable device 320 (e.g., theelectronic device 201 in FIG. 2) may include a housing (or a body). Forexample, the housing may include a portion to be detachably mounted on auser's ear, a speaker, a battery, a wireless communication circuit, amemory, or a processor.

According to an embodiment, when being seated on the charging device310, the ear-wearable device 320 may perform a charging operation basedon a voltage supplied from the charging device 310. According to anembodiment, the ear-wearable device 320 may receive, through anelectrical circuit, power transmitted from the charging device 310, andmay charge a battery based on the applied power. The ear-wearable device320 may be driven by a rechargeable/dischargeable battery.

According to an embodiment, the charging device 310 may include ahousing (or a body), and, for example, the housing may include at leastone fastening groove (e.g., a fixing member) configured to receive acommunication circuit, a power interface, a control circuit, a battery,and the ear-wearable device 320 which includes a pair of devices,including a first ear-wearable device 321 and a second ear-wearabledevice 322 that can be worn on both ears of the user, respectively.According to an embodiment, the charging device 310 may include abattery therein to charge the ear-wearable device 320 without beingconnected to a separate power supply device (not shown).

According to an embodiment, the charging device 310 may be connected toa power supply device to charge the ear-wearable device 320 regardlessof whether a battery is included therein. To this end, the chargingdevice 310 may include the charging circuit 318 for charging theear-wearable device 320.

According to an embodiment, the charging device 310 may process, basedon state information of the ear-wearable device 320, an operation ofcharging the ear-wearable device 320. For example, the charging device310 may also charge the ear-wearable device 320 by charging-leveldetection using the charging circuit 318.

Referring to FIG. 3C, the charging device 310 may include a firstmounting part 312 and a second mounting part 313, which are configuredto receive the pair of ear-wearable devices 321 and 322. For example,the first mounting part 312 may have the shape of a groove in which afirst ear-wearable device 321 is partially fitted, and likewise, thesecond mounting part 313 may have the shape of a groove in which thesecond ear-wearable device 322 is partially fitted. According to anembodiment, the first mounting part 312 may include at least onecharging contact 314. According to an embodiment, as illustrated in FIG.3, the at least one charging contact 314 in the first mounting part 312may include two-pin-type pogo pin, and may include, for example, a VBUSterminal and a GND terminal.

For example, when the first ear-wearable device 321 is mounted on thefirst mounting part 312, at least one contact 324 of the firstear-wearable device 321 may be electrically connected to the at leastone charging contact 314 of the first mounting part 312. Likewise, thesecond mounting part 313 may include at least one charging contact 315,and the at least one charging contact 315 may be electrically connectedto at least one contact of the second ear-wearable device 322.

According to an embodiment, the first ear-wearable device 321 and thesecond ear-wearable device 322 may use connection terminals (pads)formed in the respective housing to be provided with charging powerthrough an electrical connection using at least one contact 314 or 315of the charging device 310. For example, as in the perspective view ofFIG. 3B illustrating the shape of the first ear-wearable device 321 seenin a first direction, the first ear-wearable device 321 may includemultiple electrodes, and the multiple electrodes, which are connectionterminals for being provided with charging power, may be exposed to theouter surface of the housing. Further, although FIG. 3B illustrates theshape of the second ear-wearable device 322 seen in another direction,the second ear-wearable device 322 may include the same multipleelectrodes as the first ear-wearable device 321 at an opposite side tothe outer surface of the housing.

According to an embodiment, the charging device 310 may include an outerinterface (e.g., a connector) 311. For example, the outer interface maybe a USB-type connector or charging port. According to an embodiment,the charging device 310 may receive power from an external device (e.g.,a power source) through the outer interface 311.

According to an embodiment, the charging device 310 may include abattery (not shown). For example, the charging device 310 may receivepower from the external device to charge the battery. Further, when thefirst ear-wearable device 321 and the second ear-wearable device 322 aremounted on the first mounting part 312 and the second mounting part 313,respectively, a battery of each of the first ear-wearable device 321 andthe second ear-wearable device 322 may be charged by the battery of thecharging device 310.

According to an embodiment, the charging device 310 may include anindicator light 317 for indicating the battery level of the chargingdevice (or charging case), and may include an indicator light 316 forindicating the battery level of the ear-wearable devices 321 and 322.

FIG. 4 is a block diagram illustrating an example configuration of afirst charger 400 included in the charging device 310 according tovarious embodiments. Referring to FIG. 4, the charging device 310according to an embodiment may include the first charger 400. The firstcharger 400 according to an embodiment may include at least one among acurrent reference control circuit 410, a charging current controlcircuit 420, a first comparator 430, a first error amplifier 440, asecond error amplifier 450, and a first selection circuit 460. Thecharging device 310 according to an embodiment may also include acontrol signal generator which includes the current reference controlcircuit 410, the first comparator 430, the first error amplifier 440,the second error amplifier 450, and the first selection circuit 460.

The current reference control circuit 410 according to an embodiment maydetermine a first critical current value based on a signal (e.g.,high/low signal) received from the first comparator 430. For example,when a high signal is received from the first comparator 430, thecurrent reference control circuit 410 according to an embodiment maydecrease the first critical current value by a predesignated value(e.g., 50 mA). When a low signal is received from the first comparator430, the current reference control circuit 410 according to anembodiment may maintain a currently configured first critical currentvalue. The current reference control circuit 410 according to anembodiment may output (or transmit) information about the first criticalcurrent value to the first error amplifier 440.

The charging current control circuit 420 according to an embodiment maycontrol the magnitude of charging current, which is input to the firstcharger 400 from the outside, based on a third control signal receivedfrom the first selection circuit 460. The charging current controlcircuit 420 according to an embodiment may also include a current supplycircuit. In this case, the charging current control circuit 420according to an embodiment may be configured to output a chargingcurrent. The charging current control circuit 420 according to anembodiment may control a duty cycle (or a pulse width) to control themagnitude of a charging current. The third control signal according toan embodiment may include a control signal that is output from an erroramplifier having a smaller error value among an amplified error (ordifference) value included in a first control signal output from thefirst error amplifier 440 and an amplified error value included in asecond control signal output from the second error amplifier 450. Thefirst control signal, the second control signal, and the third controlsignal according to an embodiment may be analog signals. The chargingcurrent control circuit 420 according to an embodiment may adjust, forexample, the magnitude of a charging current based on a mapping table inwhich a correlation between an amplified error value and the magnitudeof an output current is defined. When the third control signal isreceived, the charging current control circuit 420 according to anembodiment may adjust the pulse width of a charging current such thatthe charging current decreased by the predetermined value (e.g., 50 mA)is applied to an interface 470. According to an embodiment, informationabout a value of the charging current having an adjusted (e.g.,decreased) magnitude, may be sensed by the first error amplifier 440.The first error amplifier 440 according to an embodiment may compare thefirst critical current value and the value of the charging currenthaving an adjusted magnitude. The first error amplifier 440 according toan embodiment may calculate an error (in other words, a difference)between the magnitude of the charging current and the first criticalcurrent value, may amplify the same according to a gain of the firsterror amplifier 440, and may output the same as a first signal to thefirst selection circuit 460.

The first comparator 430 according to an embodiment may be configured tocompare a voltage value applied to the interface 470 and a predeterminedfirst critical voltage value (e.g., a voltage value (e.g., 4.7V)increased by a predesignated value rather than a full-charge voltage(e.g., 4.35V) of the battery module 326 of the ear-wearable device 320).Alternatively, according to an embodiment, the first comparator 430 maybe configured to compare the voltage value applied to the interface 470and a voltage value that is obtained by subtracting a predesignatedoffset voltage value (e.g., 0.1V) from the predetermined first criticalvoltage value (e.g., 4.7V).

When a voltage value currently applied to the interface reaches thefirst critical voltage value (or a voltage value obtained by subtractingthe predesignated offset voltage value (e.g., 0.1V) from the firstcritical voltage value (e.g., 4.7V)), the first comparator 430 accordingto an embodiment may output a high signal (e.g., a (+) signal) to thecurrent reference control circuit 410. When a voltage value currentlyapplied to the interface does not reach the first critical voltage value(or a voltage value obtained by subtracting the predesignated offsetvoltage value (e.g., 0.1V) from the first critical voltage value (e.g.,4.7V)), the first comparator 430 according to an embodiment may output alow signal (e.g., a (−) signal) to the current reference control circuit410.

The first error amplifier 440 according to an embodiment may compare anerror between the magnitude of a charging current applied to theinterface 470 and the first critical current, and may amplify the erroraccording to a designated ratio (e.g., a gain of the first erroramplifier 440). The first error amplifier 440 according to an embodimentmay output, as the first control signal, a signal including informationabout the amplified error to the first selection circuit 460. Forexample, according to an embodiment, when the error has been amplified,a saturated value may be output as the first control signal based on thegain of the first error amplifier 440.

The second error amplifier 450 according to an embodiment may compare anerror between the magnitude of the voltage value applied to theinterface 470 and the first critical voltage value (e.g., 4.7V), and mayamplify the error according to a designated ratio (e.g., a gain of thesecond error amplifier 450). The second error amplifier 450 according toan embodiment may output, as a second control signal, a signal includinginformation about the amplified error to the first selection circuit460. According to an embodiment, when the error has been amplified(e.g., when a voltage applied to the interface 470 is 4.0V and the firstcritical voltage is 4.7V), a saturated value may be output as the secondcontrol signal based on the gain of the second error amplifier 450.

The first selection circuit 460 according to an embodiment may outputthe third control signal to the charging current control circuit 420.The third control signal according to an embodiment may include acontrol signal that is output from an error amplifier having a smallererror value among an amplified error (or difference) value included inthe first control signal output from the first error amplifier 440 andan amplified error value included in the second control signal outputfrom the second error amplifier 450. For example, when the secondcontrol signal output by the second error amplifier 450 includes, as anamplified error value, a high-level saturated value among the high-level(e.g., (+)) saturated value and a low-level (e.g., (−)) saturated valuefor the second error amplifier 450 (e.g., when the voltage applied tothe interface 470 is 4.0V, the first critical voltage value is 4.7V, andthe gain of the second error amplifier 450 is 50,000), while the firstcontrol signal output by the first error amplifier 440 includes, as anamplified error value, a value between a high-level saturated value anda low-level saturated value for the first error amplifier 440 becausethe charging current and the first critical current maintain almostidentical values by control (e.g., when the magnitude of a chargingcurrent applied to the interface 470 is 1.999 A, the first criticalcurrent value is 2.00 A, and the gain of the first error amplifier 440is 3,000, in which case the output of the first error amplifier 440 maybe 3V), the first control signal output by the first error amplifier 440may be selected as the third control signal, and the third controlsignal may be output to the charging current control circuit 420.

FIG. 5 is a block diagram illustrating an example configuration of asecond charger 500 included in the ear-wearable device 320 according tovarious embodiments. Referring to FIG. 5, the second charger 500according to an embodiment may include a MOSFET 510, a third erroramplifier 520, a fourth error amplifier 530, and a second selectioncircuit 540. The second charger 500 according to an embodiment may beelectrically connected to the battery module 326.

The MOSFET 510 according to an embodiment may be electrically connectedto the interface 470. The MOSFET 510 according to an embodiment mayfunction as a resistor. According to an embodiment, when a resistancevalue of the MOSFET 510 increases, the voltage value applied to theinterface 470 may increase. In relation to the MOSFET 510 according toan embodiment, the resistance value of the MOSFET 510 may be increasedby adjusting a gate voltage (e.g. decreasing a gate voltage) based on asixth control signal output from the second selection circuit 540. Thesixth control signal according to an embodiment may include a controlsignal that is output from an error amplifier having a smaller errorvalue among an amplified error (or difference) value included in afourth control signal output from the third error amplifier 520 and anamplified error value included in a fifth control signal output from thefourth error amplifier 530. The fourth control signal, the fifth controlsignal, and the sixth control signal according to an embodiment may beanalog signals. The second selection circuit 540 according to anembodiment, for example, may adjust a resistance value of the MOSFET 510based on a mapping table in which a correlation between an amplifiederror value and the magnitude of an output current is defined.Alternatively, after outputting the sixth control signal, the secondselection circuit 540 according to an embodiment may adjust a gatevoltage of the MOSFET 510 so as to have a resistance value increased bya predesignated value. When a current value of the battery module 326 isless than the second critical current value and when a voltage value ofthe battery is smaller than the second critical voltage value, theMOSFET 510 according to an embodiment may be fully turned on (e.g., whenthe resistance value of the MOSFET 510 is equal to or less than aspecific value). According to an embodiment, even when the resistance ofthe MOSFET 510 is infinite, a voltage value applied to the interface 470may not exceed the first critical voltage value.

The third error amplifier 520 according to an embodiment may compare anerror between the magnitude of a battery current and the second criticalcurrent value, and may amplify the error according to a designated ratio(e.g., a gain of the third error amplifier 520). The third erroramplifier 520 according to an embodiment may output, as the fourthcontrol signal, a signal including information about the amplified errorto the second selection circuit 540. For example, according to anembodiment, when the error has been amplified, a value saturated at ahigh-level (e.g., (+)) or low-level (e.g., (−)) may be output as thefourth control signal based on the gain of the third error amplifier520.

The fourth error amplifier 530 according to an embodiment may compare anerror between the magnitude of a battery voltage and the second criticalvoltage value (e.g., a full-charge voltage of a battery, 4.35V), and mayamplify the error according to a designated ratio (e.g., a gain of thefourth error amplifier 530). The fourth error amplifier 530 according toan embodiment may output, as the fifth control signal, a signalincluding information about the amplified error to the second selectioncircuit 540. According to an embodiment, when the error has beenamplified, a value saturated at a high-level (e.g., (+)) or low-level(e.g., (−)) may be output as the fifth control signal based on the gainof the fourth error amplifier 530.

The second selection circuit 540 according to an embodiment may outputthe sixth control signal to the MOSFET 510. The sixth control signalaccording to an embodiment may include a control signal that is outputfrom an error amplifier having a smaller error value among the amplifiederror (or difference) value included in the fourth control signal outputfrom the third error amplifier 520 and the amplified error valueincluded in the fifth control signal output from the fourth erroramplifier 530. For example, the fourth control signal output by thethird error amplifier 520 may include, as an amplified error value, thehigh-level saturated value among the high-level saturated value and thelow-level saturated value for the third error amplifier 520. Further,when the fifth control signal output by the fourth error amplifier 530includes, as an amplified error value, the low-level saturated valueamong the high-level saturated value and the low-level saturated valuefor the fourth error amplifier 530, the fifth control signal output bythe fourth error amplifier 530 may be selected as the sixth controlsignal, and the sixth control signal may be output to the MOSFET 510.The resistance value of the MOSFET 510 according to an embodiment may beadjusted by the sixth control signal. For example, the second selectioncircuit 540 according to an embodiment may adjust (e.g., increase) theresistance value of the MOSFET 510 using a mapping table in which acorrelation between the amplified error value and the resistance value(or gate voltage value) of the MOSFET 510 is defined. Alternatively, thegate voltage of the MOSFET 510 according to an embodiment may also becontrolled by the second selection circuit 540 so as to be adjustedbased on a predesignated value. In the second selection circuit 540according to an embodiment, when all of the fourth control signal andthe fifth control signal have high-level saturated values, the sixthcontrol signal may have the high-level saturated value included in thefourth control signal or the fifth control signal, in which case themagnitude of resistance of the MOSFET 510 may be maintained (in otherwords, the MOSFET may remain in a fully turned-on state).

FIG. 6 is diagram flowchart illustrating an example operation ofstopping (in other words, completing) charging of an external electronicdevice (e.g., the ear-wearable device 320) when a charging current valueoutput from the charging device 310 reaches a termination current valueaccording to various embodiments. FIG. 7 includes graphs illustrating anexample operation of charging a battery according to the function oroperation illustrated in FIG. 6 according to various embodiments. FIG. 7illustrates a graph 710 regarding control of a charging current, a graph720 regarding a change in an interface voltage, and a graph 730regarding a change in a battery voltage.

Referring to FIG. 6, in operation 610, the charging device 310 accordingto an embodiment may detect contact of the external electronic device(e.g., the ear-wearable device 320) with the interface 470. In operation620, the charging device 310 according to an embodiment may increase andoutput a value of a charging current for charging the battery module 326of the external electronic device (e.g., the ear-wearable device 320).FIG. 7 illustrates a function or operation 711 of outputting a chargingcurrent while increasing the magnitude thereof.

In operation 630, the charging device 310 according to an embodiment maydetermine whether a voltage value applied to the interface 470 hasreached a first critical voltage value. The charging device 310 (e.g.,the first comparator 430) according to an embodiment may sense a voltagevalue currently applied to the interface 470, and may compare the sensedvoltage value with the first critical voltage value. When the voltagevalue currently applied to the interface 470 reaches the first criticalvoltage value (630—Yes), the charging device 310 (e.g., the firstcomparator 430) according to an embodiment may output a high signal(e.g., a (+) signal) to the current reference control circuit 410. Whenthe voltage value currently applied to the interface does not reach thefirst critical voltage value (630—No), the first comparator 430according to an embodiment may output a low signal (e.g., a (−) signal)to the current reference control circuit 410. FIG. 7 illustrates thecase 721 in which an interface voltage reaches the first criticalvoltage value (e.g., 4.7V) by an increase in a resistance value of theMOSFET 510.

When the voltage value applied to the interface 470 has reached thefirst critical voltage value (e.g., 4.7V) (operation 630—Yes), thecharging device 310 according to an embodiment may decrease, inoperation 640, the charging current value until the voltage valueapplied to the interface 470 falls below the first critical voltagevalue. When a high signal is received from the first comparator 430, thecharging device 310 (e.g., the current reference control circuit 410)according to an embodiment may decrease the first critical current valueby a predesignated value (e.g., 50 mA). The charging device 310according to an embodiment may repeatedly perform operation 630 andoperation 640 until the voltage value applied to the interface 470 fallsbelow the first critical voltage value. Thus, the first critical currentvalue may be gradually/continuously decreased. FIG. 7 illustrates afunction or operation 712 by which a charging current is decreased basedon the voltage applied to the interface 470 reaching a first criticalvoltage 721 and a function or operation 713 of charging the batterymodule 326 using a charging current (e.g., 2.00A) having the decreasedmagnitude.

In operation 650, the charging device 310 according to an embodiment maydetermine whether the decreased charging current value has reached atermination current. When the decreased charging current value hasreached the termination current (650—Yes), the charging device 310according to an embodiment may complete, in operation 660, charging ofthe battery module 326 (e.g., may continuously output the currentreaching the termination current or may stop outputting of the chargingcurrent). For example, when the charging current value is less than atermination current value (e.g., 0.2 A), the current reference controlcircuit 410 may change the first critical current value to 0 to make anoutput charging current have a value of 0, thereby completing chargingof the battery module 326. When the decreased charging current value hasnot reached the termination current (650—No), the charging device 310according to an embodiment may determine, in operation 670, whether thevoltage value applied to the interface 470 has reached the firstcritical voltage value again. FIG. 7 illustrates the case 722 in whichthe voltage value applied to the interface 470 has reached the firstcritical voltage value again. When the voltage value applied to theinterface 470 has reached the first critical voltage value again(operation 670—Yes), the charging device 310 according to an embodimentmay perform operation 640 again. FIG. 7 illustrates a function oroperation 714 by which the charging current is decreased again when thevoltage value applied to the interface 470 reaches the first criticalvoltage value again. When the voltage value applied to the interface 470has not reached the first critical voltage value again (operation670—No), the charging device 310 according to an embodiment may performoperation 650 again. The above-described method of charging of thebattery module 326 can reduce the difference between an interfacevoltage and a battery cell voltage, and thus can have an advantageouseffect of reducing charging loss.

FIG. 8 is a circuit diagram illustrating example configurations of afirst charger 400 and a second charger 500 according to variousembodiments. The second charger 500 according to an embodiment mayfurther include a control circuit for controlling the MOSFET 510although the control circuit is not illustrated.

Referring to FIG. 8, the charging device 310 according to an embodimentmay include the first charger 400. The first charger 400 according to anembodiment may include at least one among a current reference controlcircuit 410, a charging current control circuit 420, a first comparator430, a first error amplifier 440, a second error amplifier 450, and afirst selection circuit 460. The current reference control circuit 410according to an embodiment may be electrically connected to the firstcomparator 430. The first comparator 430 according to an embodiment mayinclude at least one calculation amplifier. The first comparator 430according to an embodiment may be electrically connected to the seconderror amplifier 450. Each of the first error amplifier 440 and thesecond error amplifier 450 according to an embodiment may include atleast one calculation amplifier. A first critical current value may beinput into one end of the first error amplifier 440 according to anembodiment, and a charging current value may be input into the other endthereof. The first critical voltage value may be input into one end ofthe second error amplifier 450 according to an embodiment, and a voltagevalue of an interface 470 may be input into the other end thereof. Thefirst error amplifier 440 and the second error amplifier 450 accordingto an embodiment may be electrically connected to the first selectioncircuit 460. The first selection circuit 460 according to an embodimentmay include at least two diodes.

The ear-wearable device 310 according to an embodiment may include thesecond charger 500. The second charger 500 herein may include at leastone among at least one MOSFET 510, a third error amplifier 520, a fourtherror amplifier 530, a second selection circuit 540, and a batterymodule 326. The at least one MOSFET 510 according to an embodiment maybe electrically connected to the second selection circuit 540. Each ofthe third error amplifier 520 and the fourth error amplifier 530according to an embodiment may include at least one calculationamplifier. The second selection circuit 540 according to an embodimentmay include at least two diodes. A second critical current value may beinput into one end of the third error amplifier 520 according to anembodiment, and a battery current value may be input into the other endthereof. A second critical voltage value may be input into one end ofthe fourth error amplifier 530 according to an embodiment, and a batteryvoltage value may be input into the other end thereof.

FIG. 9 is a flowchart illustrating an example operation of increasingresistance of the MOSFET 510 included in the second charger 500according to various embodiments.

Referring to FIG. 9, in operation 910, the second charger 500 accordingto an embodiment (e.g., the third error amplifier 520) may calculate andamplify an error between the battery current value and the secondcritical current value to output a fourth control signal. In operation920, the second charger 500 according to an embodiment (e.g., the fourtherror amplifier 530) may calculate and amplify an error between thebattery voltage value and the second critical voltage value to output afifth control signal. In operation 930, the second charger 500 accordingto an embodiment (e.g., the second selection circuit 540) may determinewhether there is a smaller value among the fourth control signal and thefifth control signal. When there is a smaller value among the fourthcontrol signal and the fifth control signal (930—Yes), the secondcharger 500 according to an embodiment (e.g., the second selectioncircuit 540) may increase, in operation 940, the resistance of theMOSFET 510 based on the smaller value among the fourth control signaland the fifth control signal. When the resistance of the MOSFET 510according to an embodiment is increased, the voltage of the interface470 may be increased.

The electronic device according to various embodiments may be one ofvarious types of electronic devices. The electronic devices may include,for example, a portable communication device (e.g., a smartphone), acomputer device, a portable multimedia device, a portable medicaldevice, a camera, a wearable device, a home appliance, or the like.According to an embodiment of the disclosure, the electronic devices arenot limited to those described above.

It should be appreciated that various embodiments of the disclosure andthe terms used therein are not intended to limit the technologicalfeatures set forth herein to particular embodiments and include variouschanges, equivalents, or replacements for a corresponding embodiment.With regard to the description of the drawings, similar referencenumerals may be used to refer to similar or related elements. It is tobe understood that a singular form of a noun corresponding to an itemmay include one or more of the things, unless the relevant contextclearly indicates otherwise. As used herein, each of such phrases as “Aor B,” “at least one of A and B,” “at least one of A or B,” “A, B, orC,” “at least one of A, B, and C,” and “at least one of A, B, or C,” mayinclude any one of, or all possible combinations of the items enumeratedtogether in a corresponding one of the phrases. As used herein, suchterms as “1st” and “2nd,” or “first” and “second” may be used to simplydistinguish a corresponding component from another, and does not limitthe components in other aspect (e.g., importance or order). It is to beunderstood that if an element (e.g., a first element) is referred to,with or without the term “operatively” or “communicatively”, as “coupledwith,” “coupled to,” “connected with,” or “connected to” another element(e.g., a second element), the element may be coupled with the otherelement directly (e.g., wiredly), wirelessly, or via a third element.

As used in connection with various embodiments of the disclosure, theterm “module” may include a unit implemented in hardware, software, orfirmware, or any combination thereof, and may interchangeably be usedwith other terms, for example, “logic,” “logic block,” “part,” or“circuitry”. A module may be a single integral component, or a minimumunit or part thereof, adapted to perform one or more functions. Forexample, according to an embodiment, the module may be implemented in aform of an application-specific integrated circuit (ASIC).

Various embodiments as set forth herein may be implemented as software(e.g., the program 240) including one or more instructions that arestored in a storage medium (e.g., internal memory 236 or external memory238) that is readable by a machine (e.g., the electronic device 201).For example, a processor (e.g., the processor 220) of the machine (e.g.,the electronic device 201) may invoke at least one of the one or moreinstructions stored in the storage medium, and execute it. This allowsthe machine to be operated to perform at least one function according tothe at least one instruction invoked. The one or more instructions mayinclude a code generated by a complier or a code executable by aninterpreter. The machine-readable storage medium may be provided in theform of a non-transitory storage medium. Wherein, the “non-transitory”storage medium is a tangible device, and may not include a signal (e.g.,an electromagnetic wave), but this term does not differentiate betweenwhere data is semi-permanently stored in the storage medium and wherethe data is temporarily stored in the storage medium.

According to an embodiment, a method according to various embodiments ofthe disclosure may be included and provided in a computer programproduct. The computer program product may be traded as a product betweena seller and a buyer. The computer program product may be distributed inthe form of a machine-readable storage medium (e.g., compact disc readonly memory (CD-ROM)), or be distributed (e.g., downloaded or uploaded)online via an application store (e.g., PlayStore™), or between two userdevices (e.g., smart phones) directly. If distributed online, at leastpart of the computer program product may be temporarily generated or atleast temporarily stored in the machine-readable storage medium, such asmemory of the manufacturer's server, a server of the application store,or a relay server.

According to various embodiments, each component (e.g., a module or aprogram) of the above-described components may include a single entityor multiple entities, and some of the multiple entities may also beseparately disposed in different components. According to variousembodiments, one or more of the above-described components or operationsmay be omitted, or one or more other components or operations may beadded. Alternatively or additionally, a plurality of components (e.g.,modules or programs) may be integrated into a single component. In sucha case, the integrated component may still perform one or more functionsof each of the plurality of components in the same or similar manner asthey are performed by a corresponding one of the plurality of componentsbefore the integration. According to various embodiments, operationsperformed by the module, the program, or another component may becarried out sequentially, in parallel, repeatedly, or heuristically, orone or more of the operations may be executed in a different order oromitted, or one or more other operations may be added.

While the disclosure has been illustrated and described with referenceto various example embodiments, it will be understood that the variousexample embodiments are intended to be illustrative, not limiting. Itwill be further understood by those skilled in the art that variouschanges in form and detail may be made without departing from the truespirit and full scope of the disclosure, including the appended claimsand their equivalents. It will also be understood that any of theembodiment(s) described herein may be used in conjunction with any otherembodiment(s) described herein.

What is claimed is:
 1. An electronic device comprising: an interfaceincluding a conductive piece; a current reference control circuit; and acharging current control circuit configured to control a magnitude of acharging current applied to the interface based on a control signalresulting from a comparison between a charging current value applied tothe interface and a first critical current value configured in thecurrent reference control circuit, wherein the current reference controlcircuit is configured to: gradually decrease the first critical currentvalue based on a voltage value applied to the interface reaching a firstcritical voltage value, and maintain the first critical current valuebased on the voltage value applied to the interface being less than thefirst critical voltage value.
 2. The electronic device of claim 1,further comprising: a comparator configured to compare the voltage valueapplied to the interface with the first critical voltage value, whereinthe comparator is configured to output a high signal to the currentreference control circuit based on the voltage value applied to theinterface reaching the first critical voltage value.
 3. The electronicdevice of claim 1, further comprising: a first error amplifierconfigured to determine and amplify an error between the chargingcurrent value applied to the interface and the first critical currentvalue, wherein the first error amplifier is configured to output, as afirst control signal, a value of the error amplified by the first erroramplifier to a first selection circuit or a charging current controlcircuit.
 4. The electronic device of claim 3, further comprising: asecond error amplifier configured to determine and amplify an errorbetween the voltage value applied to the interface and the firstcritical voltage value, wherein the second error amplifier is configuredto output, as a second control signal, a value of the error amplified bythe second error amplifier to the first selection circuit or thecharging current control circuit
 5. The electronic device of claim 4,wherein the first selection circuit is configured to compare errorsincluded in the first control signal and the second control signal andoutput, as a third control signal, a control signal of one erroramplifier which outputs a smaller value among the value output by thefirst error amplifier and the value output by the second erroramplifier, and the charging current control circuit is configured tocontrol the magnitude of the charging current applied to the interface,based on the third control signal.
 6. The electronic device of claim 5,wherein the charging current control circuit is further configured tocontrol the magnitude of the charging current applied to the interfaceby adjusting a pulse width of the charging current based on a magnitudeof an error value included in the third control signal, based on thethird control signal being received from the first selection circuit. 7.The electronic device of claim 1, wherein the voltage value applied tothe interface is increased based on a resistance of a MOSFET included inan external electronic device being increased.
 8. The electronic deviceof claim 7, wherein the external electronic device comprises: a thirderror amplifier configured to: determine and amplify an error between abattery current value of the external electronic device and a secondcritical current value, and output a fourth control signal comprising avalue of the amplified error; a fourth error amplifier configured to:determine and amplify an error between a battery voltage value of theexternal electronic device and a second critical voltage value, andoutput a fifth control signal comprising a value of the amplified error;and a second selection circuit electrically connected to the third erroramplifier and the fourth error amplifier and configured to receive thefourth control signal and the fifth control signal, and to output asixth control signal, based on the fourth control signal and the fifthcontrol signal, wherein a resistance value of the MOSFET is controlledbased on the sixth control signal output from the second selectioncircuit.
 9. A method for controlling an electronic device, the methodcomprising: based on a voltage value applied to an interface of theelectronic device reaching a first critical voltage value, graduallydecreasing a first critical current value by a current reference controlcircuit of the electronic device until the voltage value applied to theinterface falls below the first critical voltage value; and maintainingthe first critical current value by the current reference controlcircuit of the electronic device based on the voltage value applied tothe interface being less than the first critical voltage value, whereinthe electronic device comprises: a charging current control circuitconfigured to control a magnitude of a charging current applied to theinterface based on a control signal resulting from a comparison betweena charging current value applied to the interface and the first criticalcurrent value of the current reference control circuit.
 10. The methodof claim 9, wherein the electronic device further comprises a comparatorconfigured to compare the voltage value applied to the interface withthe first critical voltage value, wherein the comparator is configuredto output a high signal to the current reference control circuit basedon the voltage value applied to the interface reaching the firstcritical voltage value.
 11. The method of claim 9, wherein theelectronic device further comprises a first error amplifier configuredto determine and amplify an error between the charging current valueapplied to the interface and the first critical current value, whereinthe first error amplifier is configured to output, as a first controlsignal, a value of the error amplified by the first error amplifier to afirst selection circuit.
 12. The method of claim 11, wherein theelectronic device further comprises a second error amplifier configuredto determine and amplify an error between the voltage value applied tothe interface and the first critical voltage value, wherein the seconderror amplifier is configured to output, as a second control signal, avalue of the error amplified by the second error amplifier to the firstselection circuit.
 13. The method of claim 11, wherein the firstselection circuit is configured to compare errors included in the firstcontrol signal and the second control signal and output, as a thirdcontrol signal, a control signal of one error amplifier which outputs asmaller value among the value output by the first error amplifier andthe value output by the second error amplifier, and the charging currentcontrol circuit is configured to control the magnitude of the chargingcurrent applied to the interface, based on the third control signal. 14.The method of claim 13, wherein the charging current control circuit isfurther configured to control the magnitude of the charging currentapplied to the interface by adjusting a pulse width of the chargingcurrent based on a magnitude of an error value included in the thirdcontrol signal, based on the third control signal being received fromthe first selection circuit.
 15. The method of claim 9, wherein thevoltage value applied to the interface is increased based on aresistance of a MOSFET included in an external electronic device beingincreased.